Shoe with an articulated spring-loaded outsole

ABSTRACT

Shoe ( 1 ), especially an athletic shoe, with a midsole ( 2 ) and an upper ( 3 ) connected to the midsole ( 2 ), the midsole ( 2 ) having a base body ( 2   a ) which is connected to the upper ( 3 ), and a bottom plate ( 2   b ). To improve the adjustability of the spring properties and/or the damping properties of the shoe sole, it is provided that at least one part ( 4, 5 ) of the bottom plate ( 2   b ) is connected to the base body ( 2   a ) by a hinge at an articulation point ( 7 ). Furthermore, at least one spring element ( 8 ) is provided between the side of the part ( 4, 5 ) of the bottom plate ( 2   b ) facing the base body ( 2   a ) and the side of the base body ( 2   a ) facing the part ( 4, 5 ) of the bottom plate ( 2   b ). Preferably, one spring is provided in the heel area and a plurality of springs are provided in the forefoot area.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The invention relates to a shoe, especially an athletic shoe, with amidsole and an upper connected to the midsole, the midsole beingconnected between a base body which is connected to the upper, and abottom plate (outsole).

2. Description of the Related Art

A shoe of this type is known from published European Patent ApplicationNo. EP 0 552 994 B1 and corresponding U.S. Pat. No. 5,282,325. The upperis connected to the base body. While the midsole is connected to anoutsole in the forward shoe area, the base body and the outsole divergefrom one another in the shape of a wedge toward the end of the shoe.Between the base body and the outsole in the heel area a torsion springis disposed between a pair of interior plates and the bottom plate candeflect relative to the outsole by compression of the spring. While theresiliency of the shoe sole can be influenced via a spring insert ofthis type, it is not possible to adjust the spring/damping propertieswith such an arrangement.

SUMMARY OF THE INVENTION

It is a primary object of the present invention is to provide a shoe,especially an athletic shoe and especially preferably a running shoe,such that it becomes possible to adjust the spring properties and/or thedamping properties of the shoe sole in a manner as defined as possibleand to adapt them to given boundary conditions as well as to changethese properties if necessary.

Furthermore, it is a further object to make it possible to influence thestability of the shoe and especially of the sole in an improved manner.

These objects are achieved by the invention in that at least one part ofthe bottom plate is located by means of a hinge at an articulation pointon the base body, between the side of the part of the bottom platefacing the base body and the side of the base body facing the part ofthe bottom plate there being at least one spring element.

Accordingly the shoe, especially the athletic shoe, therefore calls fora bottom plate which is articulated to the base body by means of ahinge, a spring element between the base body and the bottom plateinfluencing the spring and/or damping property of a midsole in apurposeful manner.

Preferably, the bottom plate has two parts which are coupled to the basebody at the same articulation point.

The base body can be made in one piece and in the shape of a shelland/or plate. This is to be understood especially as the base body forthe heel area of the shoe being made as a shell which in partthree-dimensionally encompasses the heel of the wearer, while the basebody in the forefoot area is made rather in the manner of a plate.

For articulated accommodation of the bottom plate on the base body, itis advantageously provided that the base body has at least one extensionwhich has the shape of a crosspiece, which extends in the direction tothe bottom plate, for forming the hinge and which has a hole toaccommodate the bearing journal. The bearing journal can be formed by ascrew which can be axially fixed with a nut. For stable execution of thehinge, it is preferably provided that the base body has two extensionswhich are located at a given distance and which are arranged on bothsides and off-center relative to the lengthwise axis of the shoe.

At least one part of the bottom plate can be made as bent and/or curvedplate which continuously widens in the direction of the articulationpoint at least over part of its extension transversely to the lengthwiseaxis of the shoe. Accordingly, most of the part of the bottom platewould be made essentially as a thin plate which according to therequired shoe contour is bent or curved and which, moreover, becomesthicker in the direction to the articulation point.

The side of the bottom plate facing the ground can be provided with aconventional outer sole, especially with a rubber sole, and it can beboth cemented separately onto the bottom plate and also can be directlyinjected-molded on.

The stability of the sole can be increased by the base body, on its sidefacing the bottom plate, bearing a guide element which interacts with anopposing guide element which is located on the side of the bottom platefacing the base body, the guide element and the opposing guide element,upon interaction, preventing or limiting the relative displacement ofthe base body and the bottom plate transversely relative to thelengthwise axis of the shoe. The guide element and the opposing guideelement can be formed by crosspiece-like elevations which are located onthe base body or on the bottom plate and which can be caused to engageone another such that relative displacement of the two partstransversely relative to the lengthwise axis of the shoe is prevented.

The execution of the spring element which is being used acquires majorimportance. It can have at least a cylindrical or prismatic shape insections, circular and polygonal cross sectional shapes being alsopossible.

Preferably, the spring element or each spring element is formed of twosections which are connected to one another, the two sections beinglocated coaxially with respect to one another and having a shape whichis congruent to one another and a section in a profile perpendicular toa vertical line having smaller dimensions than the other section. When aforce acts on the spring element, therefore when the sole is loaded bythe weight of the wearer, one possible result is that the section whichhas been made with smaller dimensions, at least in part, enters theinterior of the section which has been made with larger dimensions;accordingly the spring element which is made in this way works in themanner of a shock absorber (piston-cylinder system).

Furthermore, it can be provided that the two sections of the springelement are connected to one another via an elastic connecting sectionwhich extends only between the two sections.

It has proven especially effective when the two sections, in a profileperpendicular to the vertical, have a polygonal, especially a hexagonalshape. The two sections and the connecting section of the spring elementare made in one piece according to one development.

With respect to the number and arrangement of the spring elements, ithas proven advantageous for there to be a single spring element in theheel area between the base body and the bottom plate, preferably underthe heel bone and the heel contact area. Here, there can be several,especially three spring elements, between the base body and the bottomplate in the forefoot area, preferably under the ball of the great toe,the ball of the little toe and in the toe region.

The spring elements can be cemented, welded, mechanically connected, orconnected in situ (for example, by joint injection molding in theproduction process) to the base body and/or to the bottom plate.

Preferably, the articulation point of the hinge—viewed in the directionof the lengthwise axis of the shoe—is located in the area of themetatarsal bone, especially roughly in the area of the transition of therear third of the length of the sole to its middle third.

To reliably hold the spring element in the base body or in the bottomplate, it can be provided that the base body and/or the bottom plate hasat least one receiver for interlocking accommodation of the springelement.

Furthermore, the bottom plate can have recesses which are matched to theshape of the spring elements in a profile perpendicular to the vertical.In this way, it becomes possible to save weight, on the one hand, and onthe other hand, the spring element can thus be made visible fromunderneath. These recesses can be re-filled with transparent plasticmaterial.

In order to be able to influence the torsion and flexibility propertiesof the sole and to enable adjustment of them in a purposeful manner, itcan be provided that at least part of the bottom plate has a slot or agroove which extends preferably over the entire thickness of the bottomplate. The slot can extend over at least two thirds of the length of thepart of the bottom plate measured in the lengthwise direction of theshoe and runs roughly in the middle, essentially in the lengthwisedirection of the shoe and zig-zag in the part. Furthermore, the slot canbe filled with a material which is soft relative to the material of thepart of the bottom plate.

With respect to the material of the sole components, it has proveneffective when the base body and/or the bottom plate and/or the springelement are made of plastic, especially of a thermoplastic material,preferably of polyamide, polyurethane, polyethylene, polypropylene,polybutane, polyvinyl chloride or a mixture of at least two of theseplastics. The plastic preferably has a Shore hardness between 75A and65D; it can be transparent or translucent.

Here, it is especially preferred that the sole does not have any foamedplastic as is normally used for a midsole; therefore it is a foamlesssole.

One embodiment of the invention is shown in the drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view of an athletic shoe in accordance with anembodiment of the invention,

FIG. 2 is a bottom plan view of the bottom plate together with the hingeas seen viewed along line A-B in FIG. 1,

FIG. 3 is an exploded perspective view the base body together with thehinge, bottom plate and a spring element,

FIG. 4 is a perspective view of a spring element,

FIG. 5 is a sectional view of the spring element taken along line C-D inFIG. 4;

FIG. 6 is a perspective view of a rear foot bottom plate, and

FIG. 7 is a cross-sectional view taken along line E-F of FIG. 6.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 shows a shoe 1 of the type which is used as a running shoe andwhich, as is conventional, has an upper 3. Underneath (for orientation,the direction of the upward vertical arrow V is shown) upper 3 is amidsole designated 2 as whole. Affixed to the underside of the midsole 2is the outer sole 14, which is in the form of a rubber sole.

The midsole 2 is foamless, i.e., it does not have any foamed material,especially any foamed plastic materials, in contrast to a typicalmidsole which is formed entirely or to a substantial extent of foamedplastic material.

The midsole of the present invention is comprised of a base body 2 awhich is permanently connected to the upper 3, and of a bottom plate 2 bwhich is located below the base body 2 a, to the underside of which theouter sole 14 is attached. The bottom plate 2 b, here, is formed of twoparts 4, 5, specifically, a part 4 in the form of a rear foot bottomplate and a part 5 in the form of a forefoot bottom plate.

The two parts 4, 5 are articulated to the base body 2 a by means of ahinge 6 at an articulation point 7. For this purpose, a hinge 6 has abearing journal 12 which is oriented perpendicular to the lengthwiseaxis 13 of the shoe 1.

The articulation point 7—viewed in the direction of the lengthwise axis13 of the shoe 1—lies roughly in the area of the metatarsal bone,specifically roughly in the area of the transition of the rear third ofthe length of the midsole 2 to its middle third.

This configuration results in that, when the shoe 1 is being used, theparts 4, 5, depending on the loading of the shoe by the weight of thewearer, can pivot relative to the base body 2. The pivoting of theseparts is determined by the spring elements 8 which are located betweenthe base body 2 a and the parts 4, 5. At a given load on the shoe 1 oron the through sole 2 by the weight of the wearer, the spring anddamping behavior of the spring elements 8 determines the extent of thepivoting motion of the parts 4, 5 relative to the base body 2 a.

In FIGS. 2 & 6, it can be recognized that there is a single springelement 8 in the rear foot area which is covered by the part 4. Here,only a single receiver 20 is shown which is matched to the outer crosssectional shape of the spring element 8 (in this case, the hexagonalshape of the spring element 8). As can be seen in FIG. 7, the receiver20 has an elevation 27 which is round in cross section, which rises outof the base contour 28 of the rear part 4, and which in the interior hasa shoulder 20 a and which is made according to the outside contour ofthe spring element 8. The spring element 8 can thus be inserted into thereceiver 20 and is securely supported there on the shoulder 20 a, asindicated by the broken line illustration of a portion of spring element8 in FIG. 7.

In the forefoot area which is covered by the part 5, there are threespring elements 8, for each of which a respective receiver 20 isprovided. The receivers of the forefoot part 5 can be of the sameconstruction as that described for the receiver 20 of the rear part 4.

As can be further seen, the parts 4, 5, have recesses 21 within thereceivers 20 and which extend through the parts 4, 5. The recesses 21make it possible for the spring element 8 to be viewed from underneath.The recesses 21 have a shape corresponding to the spring elements 8.

The torsion and flexibility properties of the midsole 2 can beinfluenced by a slot 22 which can likewise be seen in FIG. 2. The slot,in the illustrated embodiment, runs over a large part sole part 5 in thedirection of the lengthwise axis 13, in a zig-zag or sinusoidal shape,roughly in the middle of the part 5. The slot 22 can also be refilledwith a material which is softer than the material of the bottom plate 2b; this enables exact adjustment of the torsion and flexibilityproperties of the midsole 2.

The interaction of the individual components of the midsole 2 is bestdiscerned from FIG. 3. The base body 2 a is made shell-shaped in therear area of the foot, therefore in the heel area, and encompasses theheel of the wearer three-dimensionally, by which the foot has goodsupport there. In the forward area of the foot, the base body 2 a ismade rather plate-shaped; it has only a slight curvature here which ismatched to the contour of the foot in this area. In the area of thearticulation point 7, therefore where the hinge 6 is located, the basebody 2 a has two downward extensions 9, 10, which project downward overthe base contour of the base body 2 a and have holes 11 which are usedfor passage of the bearing journal 12.

The two parts 4, 5 of the bottom plate 2 b are likewise largelyplate-shaped, the plate thickness being roughly 2 to 7 millimeters. Theparts 4, 5 are made slightly arched according to the ergonomics of thefoot during rolling. The two parts 4, 5 thicken in the direction towardthe articulation point 7. The hinge 6 is formed by bringing together theends of the two parts 4, 5 with the two extensions 9, 10 of the basebody 2 a. In doing so, the bearing journal 12 in the form of a screwpasses through holes 23 in the part 4 of the bottom plate 2 b, throughthe holes 11 in the extensions 9, 10 and through the hole 24 in the part5 of the bottom plate 2 b. As a result, the two extensions 9, 10 come torest in the two receiving spaces 25 which are marked in FIG. 2. Thebearing journal 12 is axially fixed with a nut 26.

As can be seen from a combined viewing of FIGS. 2 and 3, there is aguide element 15 which extends in the shape of a crosspiece on the basebody 2 a and which interacts with an opposing guide element 16 which islocated on the facing surface of part 5 of the bottom plate 2 b and iscomposed of two crosspieces which are located next to one another at amutual spacing such that the guide element 15 can just enter betweenthem. This results in that, when the two elements 15, 16 interact, anyrelative motion of the base body 2 a with respect to the part 5 of thebottom plate 2 b transversely to the direction of the lengthwise axis 13of the shoe 1 is prevented or at least limited.

The execution of the spring elements 8 follows from FIGS. 4, 5. Thespring elements 8 being used in the embodiment have a hexagonal outsidecontour having a lower section 17 and a section 18 located above it. Thetwo sections 17, 18 are joined to one another via a connecting section19. As can be seen especially from FIG. 5, the two sections 17, 18 andthe connecting section 19 are made in one piece, i.e., the entire springelement 8 is preferably produced by a single injection molding process.

When the spring element 8 is loaded by the weight of the wearer of theshoe the loading force acts vertically on the element. The smaller uppersection 18 dips into the interior of the lower section 17. The springelement 8 acts here in the manner of a piston and cylinder unit. Boththe spring constant and also the damping properties of spring element 8can be adjusted almost at will and can be matched to requirements by thegeometrical dimensions (size, height, thickness of the sections 17, 18,19) and by the choice of the material of the spring element 8. For thematerial of the spring elements 8, TPU with a Shore hardness between 70and 95 A has proven effective.

The spring elements 8 can be held essentially interchangeably—optionallytogether with the bottom plate 2 b. By replacing the elements, thespring properties of the midsole 2 and its damping intensity can beadjusted. Furthermore, the stability of midsole 2, and thus of the shoe1, can be influenced in this way.

While in the embodiment there is only a single spring element 8 in therear foot area, i.e., in the area of the part 4 of the bottom plate 2 b,several, for example, two or three spring elements 8, can be housedhere. The three illustrated spring elements have proven effective in theforefoot area, specifically one in the area of ball of the great toe, ofthe ball of the little toe and in toe region.

It is also possible for the spring elements 8 to be connected detachablyor permanently to the base body 2 a or the bottom plate 2 b. Forexample, the techniques of cementing, welding, mechanical joining orjoining in the production process (in situ) by joint injection moldingare possible, as is a combination of these possibilities.

Furthermore, the spring elements 8 can be welded on the end on one orboth sides so that an air cushion is formed in their interior. For aone-sided opening, they can lie in the direction of removal from theinjection molding tool.

Another possibility which, however is not shown in the figures, is thatthere are several spring elements 8 which gradually become smaller indimensions, interleaved in one another. As a result of the parallelconnection of the interleaved spring elements high spring stiffness canthus be achieved; this enables better absorption of forces.

It can be seen in FIG. 1 that the part 5 of the bottom plate 2 b in theforward end area, therefore in the area of the tip of the foot, hascontact with the base body 2 a. Since when the foot rolls, as a resultof the deformation of the individual sole components, a relative changeof the length of the base body 2 a and the bottom plate 2 b occurs, inthis case, it is recommended that there be a movable guide between thebase body 2 a and the bottom plate 2 b in the area of the tip of thefoot in order to equalize the aforementioned relative change of length.

Alternatively or in addition, it can also be provided that the part 5 ofthe bottom plate 2 b in the hinge 6 be supported by means of anelongated hole so that the part 5 can move a small amount in thedirection of the lengthwise axis 13 in order to equalize the changes oflength. In this case, it is also easily possible, as an alternativeconfiguration to the approach shown in FIG. 1, to provide a permanentconnection between the base body 2 a and the part 5 of the bottom plate2 b in the area of the tip of the foot.

1. Shoe, comprising: an upper and a midsole connected to the upper, themidsole having a base body which is connected to the upper and a bottomplate, wherein at part of the bottom plate is connected by a hinge at anarticulation point on the base body, wherein at least one spring elementis provided between a side of the part of the bottom plate facing thebase body and the side of the base body facing the bottom plate.
 2. Shoeas claimed in claim 1, wherein the bottom plate comprises two partswhich are coupled to the base body at said articulation point.
 3. Shoeas claimed in claim 1, wherein the base body is made in one piece and isat least partially in the shape of a shell or plate.
 4. Shoe as claimedin claim 1, wherein the hinge comprises at least one extension on in theshape of a crosspiece which has a hole for accommodating a bearingjournal.
 5. Shoe as claimed in claim 4, wherein the bearing journal isformed by a screw which is axially fixed with a nut.
 6. Shoe as claimedin claim 4, wherein the hinge has two extensions on the base body whichare located at a given distance and which are arranged on both sides andoff-center relative to the lengthwise axis of the shoe.
 7. Shoe asclaimed in claim 1, wherein at least part of the bottom plate is madeformed by a curved plate which widens continuously in a direction towardthe articulation point at least over part of the transverse extension ofthe shoe.
 8. Shoe as claimed in claim 1, wherein a side of the bottomplate facing the ground an outer sole of resilient material providedthereon.
 9. Shoe as claimed in claim 1, wherein the base body has aguide element on its side facing the bottom plate, the guide elementbeing positioned relative to an opposing guide element on the side ofthe bottom plate facing the base body such that the guide element andthe opposing guide element interact so as to at least limit relativedisplacement of the base body with respect to the bottom platetransversely with respect to the lengthwise axis of the shoe.
 10. Shoeas claimed in claim 1, wherein the spring element, at least in sections,has a cylindrical or prismatic shape.
 11. Shoe as claimed in claim 10,wherein the spring element has two sections which are connected to oneanother, the two sections being located coaxially relative to oneanother and having a shape which is congruent to one another with onesection, in a profile perpendicular to a vertical line, having smallerdimensions than the other section.
 12. Shoe as claimed in claim 11,wherein the section with smaller dimensions is able enter the interiorof the section with larger dimensions, at least in part, when a forceacts on the spring element.
 13. Shoe as claimed in claim 11, wherein thetwo sections are connected to one another via an elastic connectingsection which extends only between the two sections.
 14. Shoe as claimedin claim 11, wherein the two sections in a profile perpendicular to avertical line have a polygonal shape.
 15. Shoe as claimed in claim 13,wherein the two sections and the connecting section are made in onepiece.
 16. Shoe as claimed in claim 1, wherein a single spring elementis provided in the heel area between the base body and the bottom plate.17. Shoe as claimed in claim 1, wherein a plurality of spring elementsare provided in the forefoot area between the base body and the bottomplate.
 18. Shoe as claimed in claim 1, wherein the spring elements areconnected to at least one of the base body and the bottom plate by atleast one of being cemented, welded, mechanically connected, andconnected in situ.
 19. Shoe as claimed in claim 1, wherein thearticulation point, viewed in the direction of the lengthwise axis ofthe shoe, is located in the area of the metatarsal bone.
 20. Shoe asclaimed in claim 1, wherein at least one of the base body and the bottomplate has at least one receiver for interlocking accommodation of arespective spring element.
 21. Shoe as claimed in claim 1, wherein thebottom plate has recesses which are matched to the shape of the springelements in a profile perpendicular to a vertical line.
 22. Shoe asclaimed in claim 21, wherein the recesses are filled with a transparentplastic material.
 23. Shoe as claimed in claim 1, wherein at least onepart of the bottom plate has a slot or a groove which extends over theentire thickness of the bottom plate.
 24. Shoe as claimed in claim 23,wherein the slot extends over at least two thirds of the length said atleast one part of the bottom plate in the lengthwise direction of theshoe and runs roughly in the middle in the lengthwise direction of theshoe in a zig-zag or sinusoidal manner.
 25. Shoe as claimed in claim 23,wherein the slot is filled with a material which is soft relative to thematerial of said at least one part of the bottom plate.
 26. Shoe asclaimed in claim 1, wherein at least one of the base body, the bottomplate and the spring element is made of plastic selected from the groupconsisting of polyamide, polyurethane, polyethylene, polypropylene,polybutane, polyvinyl chloride and a mixture of at least two thereof.27. Shoe as claimed in claim 26, wherein the plastic has a Shorehardness between 75A and 65D.
 28. Shoe as claimed in claim 26, whereinthe plastic is transparent or translucent.
 29. Shoe as claimed in claim26, wherein the midsole is free of foamed plastic.